Analog Devices Inc./Maxim Integrated MAX17050X+CF0

Overview

The MAX17050X+CF0 from Maxim Integrated is a 1-cell lithium-ion battery fuel gauge IC implementing the ModelGauge m3 algorithm, delivering ±1% state-of-charge (SOC) accuracy across temperature (-40°C to +85°C), aging, and discharge-rate variations. It integrates precision coulomb counting with voltage-based open-circuit voltage (OCV) estimation, supports ratiometric thermistor-based temperature sensing via AIN/THRM, and communicates over I²C. It is deployed in space-constrained portable electronics requiring reliable runtime prediction.

For engineers reviewing the MAX17050X+CF0 datasheet, MAX17050X+CF0 pinout, MAX17050X+CF0 application, or MAX17050X+CF0 equivalent, key selection considerations include its 0.4mm-pitch 9-bump WLP package, 25µA active current, no-calibration-required measurement system, AtRate capacity estimation, and dual SOC reporting (SOCREP/SOCAV) for application-aware power management.

Technical Context

The MAX17050X+CF0 employs a servo-mixing architecture that continuously weights OCV-based state estimation against coulomb-count results-initially favoring OCV at power-up, then shifting dominance to coulomb count as cycle history accumulates. Its internal 12-bit ADC measures VBATT (2.5–4.98V full-scale, ±7.5mV error), current (±51.2mV full-scale, ±1.5µV offset), and ratiometric AIN (0.0244% FS resolution, ±0.5% accuracy).

It features dedicated hardware for battery removal detection (VAIN threshold tracking), THRM-controlled thermistor bias switching (8.48ms precharge), and ALRT-driven interrupt signaling for SOC/voltage/temperature events. The device operates from 2.5V to 4.5V, delivers 1.5–1.9V REG output, and maintains timing accuracy within ±3.5% across –20°C to +70°C.

Key Specifications

Pinout & Package

The MAX17050X+CF0 is housed in a lead(Pb)-free, 0.4mm pitch, 9-bump Wafer-Level Package (WLP), optimized for low-profile portable applications. No exposed pad; all bumps are functional terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fuel-gauge applications.

Compared with BQ27426YZFT, MAX17050X+CF0 eliminates characterization dependency and delivers tighter SOC accuracy across temperature extremes; versus MAX17055G+T, it trades protection features for minimal footprint-making it ideal for thin-profile smartphones and wearables where PCB area is premium.

Availability

The MAX17050X+CF0 is available at Aetrix Electronics and suitable for smartphones, wireless speakers, and medical wearables requiring stable component supply, long-lifecycle support, and guaranteed WLP package availability through 2030.

Supply support for MAX17050X+CF0 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated, now part of Analog Devices, designs precision analog, mixed-signal, and power-management ICs for demanding industrial, medical, and portable applications.

The MAX17050X+CF0 belongs to Maxim's ModelGauge m3 fuel-gauge product line, engineered specifically for high-accuracy, maintenance-free battery monitoring in compact Li-ion-powered devices where runtime predictability directly impacts user experience.

FAQ

What is the primary function of the MAX17050X+CF0 in a battery management system?

The MAX17050X+CF0 serves as a standalone 1-cell Li-ion fuel gauge IC that reports accurate state-of-charge (SOC), time-to-empty, remaining capacity (in mAh and %), and battery age metrics. It does not provide cell protection or charging control-its role is purely metrological, delivering calibrated measurements to the host microcontroller via I²C. Unlike basic coulomb counters, the MAX17050X+CF0 achieves this without requiring full/empty calibration cycles or relaxed battery states.

Does the MAX17050X+CF0 require external calibration during manufacturing or field use?

No, the MAX17050X+CF0 requires no external calibration. Its precision 12-bit ADCs, factory-trimmed references, and ModelGauge m3 algorithm eliminate production-line calibration steps. The device self-adapts to cell aging and temperature effects autonomously-learning capacity fade and adjusting OCV modeling during normal charge/discharge cycles. Host firmware only needs to read registers; no compensation coefficients or characterization files are required for baseline operation.

How does the MAX17050X+CF0 handle battery temperature measurement?

The MAX17050X+CF0 measures battery temperature using an external NTC thermistor in a ratiometric configuration. The THRM pin actively biases the thermistor network during conversion, while AIN reads the resulting voltage divider ratio. This ratiometric method cancels supply-voltage drift effects, achieving ±0.5% measurement accuracy. The 8.48ms THRM precharge time ensures stable settling, and bias is disabled between readings to minimize current draw-critical for long-shelf-life applications.

Can the MAX17050X+CF0 be used in multicell battery packs?

The MAX17050X+CF0 is specified and characterized exclusively for single-cell Li-ion applications (2.5V–4.5V). While the MAX17047 variant supports multicell configurations via external voltage dividers (e.g., with MAX9910 buffering), the MAX17050X+CF0's WLP package and internal design do not support safe or accurate multicell operation. Attempting to use it with stacked cells risks incorrect SOC calculation, premature shutdown, or undervoltage damage-use only in 1S configurations per datasheet specifications.

What distinguishes the MAX17050X+CF0 from the MAX17047 in practical design terms?

The MAX17050X+CF0 and MAX17047 share identical ModelGauge m3 firmware and electrical specifications but differ physically: MAX17050X+CF0 uses a 0.4mm-pitch 9-bump WLP (≈1.2mm²), while MAX17047 uses a 3mm×3mm 10-pin TDFN. Key functional differences include VTT pin omission (MAX17050X+CF0 ties VTT internally to VBATT) and absence of EP pad. Designers choose MAX17050X+CF0 for ultra-thin, space-constrained layouts; MAX17047 where thermal dissipation, thermistor sharing, or multicell support is needed.